This technical report applies to enclosed low-voltage switchgear and controlgear assemblies manufactured according to IEC 61439-2. The purpose of this technical report is to give guidance on the method of testing of enclosed low-voltage switchgear and controlgear assemblies under the conditions of arcingin air due to an internal fault. The purpose of this test is to assess the ability of the assembly to limit the risks of personal injury and damage of assemblies resulting from an internal arcing fault.